---
title: "GStreamer"
date: 2020-02-08T20:46:36-05:00
draft: false
images: []
---

GStreamer is a pipeline based multimedia framework that goes from capture, processing, to a sink such as a X window or UDP sink.

To install on Ubuntu run,

```bash
sudo apt install gstreamer1.0-tools
```

Pipelines are indicated via `!`.

To capture your webcam feed and display it in a X window, run the following:

```bash
gst-launch-1.0 v4l2src device=/dev/video0 ! videoconvert ! ximagesink
```

For the PiCar project I'm on, I need to send the video from the raspberry pi over the network as fast as possible. The next couple commands have options that reflect this.

On the PiCar, I send h264 video over the network. You might need to install an additional package for h264 encoding to work.

```bash
sudo apt install gstreamer1.0-plugins-ugly
```

To send h264 video over the network,

```bash
gst-launch-1.0 v4l2src device=/dev/video0 ! videoconvert ! x264enc ! rtph264pay ! udpsink host=192.168.0.2 port=5000
```

To send it as fast as you can,

```bash
gst-launch-1.0 v4l2src device=/dev/video0 ! videoconvert ! x264enc interlaced=true tune=zerolatency speed-preset=ultrafast ! rtph264pay ! udpsink host=192.168.0.2 port=5000
```

To receive it and display it on an X-window,

```bash
gst-launch-1.0 -v udpsrc port=5000 ! application/x-rtp,payload=96 ! rtph264depay ! decodebin ! videoconvert n-threads=4 ! ximagesink
```